Meeting Abstract
Linking phenotypic variation to underlying genetic diversity contributes to a better understanding of how evolutionary forces affect natural populations. We investigate the genetic structure and evolutionary history of red-eyed treefrogs (Agalychnis callidryas) occupying six regions along the Pacific coast of Costa Rica, where a phenotypic cline extends from the north (orange legs) to the south (purple legs), with intermediate color patterns in central regions. Patterns of color variation in intermediate central regions could be explained by the retention of ancestral color polymorphism, or by hybridization between divergent populations that meet at secondary contact zones. Comparison of RAD-sequencing and color pattern data shows patterns of genetic isolation by distance across color pattern boundaries. We present multiple incongruent patterns of phenotypic and genetic variation, which suggest the possibility of selective pressures acting on color pattern phenotype along the Pacific Coast. Overall our data support color pattern polymorphism due to differential retention of ancestral polymorphism as opposed to recent introgression.
